阅读说明：本技术 上跨在建铁路路堑公路桥箱梁多机协同吊装系统及工艺 (Multi-machine cooperative hoisting system and process for box girder of over-built railway cutting highway bridge ) 是由 俞剑 熊华涛 杨涛 石运庆 杜英杰 王超 谌文玉 惠可震 聂成燕 李盼盼 陈世钊 于 2020-06-30 设计创作，主要内容包括：本发明涉及上跨在建铁路路堑公路桥箱梁多机协同吊装系统及工艺,该方法借助于位于桥头既有道路(8)的堑顶工位起重机A(40)及在桥址吊装区域处的路基工位起重机C(2)与路基工位起重机B(3),桥址旁设置预制梁场,在梁场与桥址之间设置有用于运送箱梁(1)至吊装区域的炮车(38)；在箱梁(1)两端预设有A吊点(9)及B吊点(10)；在桥墩(4)中间预设有中间跨(5),中间跨(5)两端有边侧跨(6),堑顶工位在路基边坡坡顶处；本发明设计合理、结构紧凑且使用方便。(The invention relates to a multi-machine cooperative hoisting system and a process for box girders of a railway cut highway over a built-in bridge, wherein a prefabricated beam yard is arranged beside a bridge site by means of a cut top station crane A (40) positioned on an existing road (8) at a bridge head, a roadbed station crane C (2) and a roadbed station crane B (3) at a hoisting area of the bridge site, and a gun carriage (38) for transporting the box girders (1) to the hoisting area is arranged between the beam yard and the bridge site; a hoisting point (9) and B hoisting point (10) are preset at two ends of the box girder (1); a middle span (5) is preset in the middle of the pier (4), side spans (6) are arranged at two ends of the middle span (5), and a cutting station is arranged at the top of a roadbed side slope; the invention has reasonable design, compact structure and convenient use.)

1. A multi-machine cooperative hoisting process for a box girder of a road cutting bridge of an overpass under construction is characterized in that: by means of a trench station crane A (40) positioned at the top of a roadbed slope and a roadbed station crane C (2) and a roadbed station crane B (3) positioned at a bridge site hoisting area, a prefabricated beam field is arranged at the trench roof beside the bridge site, and a gun truck (38) for conveying a box beam (1) to the hoisting area is arranged between the beam field and the bridge site;

a hoisting point (9) and B hoisting point (10) are preset at two ends of the box girder (1); a middle span (5) is preset in the middle of the pier (4), side spans (6) are arranged at two ends of the middle span (5), and the position of a slope top of the roadbed side slope at the cutting station is cut;

the method comprises the following steps;

step one, executing a side span box girder hoisting scheme; firstly, a roadbed station crane C (2) and a roadbed station crane B (3) are both positioned on a roadbed, and a moat station crane A (40) is positioned at a cushion top; determining a station position according to the operation condition and the performance parameters of the crane; then, a gun carriage (38) is used for pushing the delivery box girder (1) backwards from the existing road (8) at the bridge head, when the left end of the girder approaches to the bridge platform, a graben station crane A (40) hooks a lifting point A (9) at the left end of the box girder to test lifting, after safety and stability are confirmed, lifting is started, and the tail of the gun carriage (38) is withdrawn; secondly, the graben station crane A (40) is matched with the gun carriage (38) to continue to translate the delivery box girder; thirdly, when the gun carriage (38) approaches the bridge platform, the roadbed station crane B and the roadbed station crane C hook the lifting point A (9) at the left end of the box girder through the balance beam, the graben station crane A changes the hook and hooks the lifting point B (10) at the right end of the box girder (1), and after the lifting point conversion is realized, the gun carriage (38) is evacuated; afterwards, the roadbed station crane B, C and the cutting station crane A cooperatively operate to translate the box girder to be in place;

step two, executing a mid-span box girder hoisting scheme; firstly, a gun carriage is used for reversely pushing a delivery box girder along an existing road and an erected side span box girder at the bridge head; then, when the left end of the box girder (1) to be hoisted approaches the left end of the right cross box girder in the first step, the roadbed station crane B hooks the hoisting point A (9) at the left end of the box girder, and the tail of the gun carriage is withdrawn; secondly, continuously translating the delivery box girder by the roadbed station crane B in cooperation with the gun carriage; thirdly, when the gun carriage approaches the left end of the right span box girder in the first step, the roadbed station crane C hooks a lifting point A (9) at the left end of the box girder, the roadbed station crane B changes the hook and hooks a lifting point B (10) at the right end of the box girder, and after the lifting point conversion is realized, the gun carriage is withdrawn; later, the box girders are translated into position by the two machines of the roadbed station crane B, C in cooperation.

2. The multimachine cooperative hoisting process of the box girder of the railway cutting highway bridge spanned over the under-construction according to claim 1, which is characterized in that: before the step one, the method comprises the following steps:

step A, determining the position of a lifting point, namely, ensuring that positive and negative bending moments at the lifting point are equal based on the distance between the lifting point and two ends of an object by taking the moment balance of a box girder as a calculation standard, wherein the two lifting points are respectively arranged at a position 0.2L away from the girder end, and the lifting point adopts a steel wire rope binding pocket hanging type;

b1, selecting the types of the roadbed station crane B and the roadbed station crane C;

firstly, the lifting capacity requirements of the roadbed station crane B and the roadbed station crane C are the same, and both are

G_jBc＝K₁K₂G₀(3.1)

In the formula, G₀The sum of the weight of the hoisted objects, the lifting lugs and the rigging shared by the crane; k₁Taking the dynamic load coefficient as 1.1; k₂Taking 1.2 as the imbalance coefficient of double-crane lifting;

then, determining the operation amplitude R of the roadbed station crane B_BHeight H of lift_B(ii) a Operation range R of roadbed station crane C_CHeight H of lift_CSame as H_B；

According to G_jBC、R_B、H_B、R_C、H_CConsidering that the cranes B, C are of the same type, determining a roadbed station crane B and a roadbed station crane C by referring to crane performance parameters;

step B2, selecting type A of the graben station crane

Firstly, according to the performance parameters of a roadbed station crane B and a roadbed station crane C; the lifting capacity requirement of the crane B, C after the lifting point conversion is that

G_jBc＝K₁K₂G₀(3.2)

In the formula, G₀The sum of the weight of the hoisted objects, the weight of the lifting lugs and the weight of the rigging shared by the roadbed station crane B and the roadbed station crane C; k₁、K₂Respectively taking a dynamic load coefficient and an unbalance coefficient, and respectively taking 1.1 and 1.2; according to the performance parameters of the automobile crane, determining that the operating working condition selects the working condition of lifting capacity G and arm length L, and the lifting height H, which corresponds to the maximum working amplitude R;

then, the calculation can obtain that the minimum working amplitude R of the crane A is required to realize the lifting point conversion of the working condition CB2 crane B, C and the crane A_A(ii) a The lifting capacity of the crane A is calculated by the same formula (3.1), and Gj can be obtained_ASelecting an automobile crane according to crane performance parameters;

step C, selecting the type of the steel wire rope

First, the use criteria of the large diameter wire rope are

In the formula, D is the minimum diameter which is required to be met by the hoisting steel wire rope; q is the bearing weight of the crane; beta is a load distribution coefficient, and is generally 66%; considering the unbalanced coefficient K of the double-crane lifting, the general value is 1.2, and the value is taken under the working condition of the multi-crane lifting

Q＝80.6×1.2＝96.7t,

Then, D is calculated from the formula (2)_min；

Secondly, the single-sided single-strand wire rope is stressed by F_NCalculated by the following formula

In the formula, 1.05 is an included angle coefficient; q is the bearing weight of the crane sling;

sum of tensile forces

Z_n＝K×F_N(4)

In the formula, k is the safety coefficient of hoisting the steel wire rope, and 10 is taken;

thirdly, the steel wire rope is a fiber core, so the breaking tension is converted into a conversion formula

Wherein α is a conversion coefficient, 1.226 is taken, and breaking force is calculated as

Wherein Z is breaking tension; f_CTaking 1670kg/mm as tensile strength of the steel wire rope²；

Through the analysis and calculation, the steel wire rope selects phi 65-6 multiplied by 19zs + FC-1670;

step D, calculating the bearing capacity of the landing leg foundation,

firstly, according to the hoisting scheme, the load bearing capacity of the crane C, B is equal; the total bearing weight N of a single crane foundation is calculated according to the following formula

In the formula, gamma_G、γ_QTaking the static load and dynamic load combination coefficients as 1.2 and 1.4 respectively; g₀The sum of the weight of the crane, the super-lifting counterweight, the sling and the rigging is same for the model B, C of the crane, G_LIs the weight of the box girder;

then, assuming that the four legs of the crane are uniformly stressed, the average compressive stress applied to the foundation by each leg is

Wherein A is the area (m) of the steel backing plate of the crane support leg²)；

Secondly, considering the construction of the upper-span railway girder erection and taking 1.2 times of safety coefficient, the bearing capacity requirement of the operation site is f_aThe bearing capacity of the foundation on site can not meet the requirement, and a treatment measure of tamping or replacing and filling can be adopted;

step E, hoisting safety analysis

Firstly, the crane anti-overturning stability standard is

∑M＝K_G·M_G+K_Q·M_Q+K_W·M_W≥0 (9)；

Wherein ∑ M is the anti-overturning moment, K_GTaking 1 as a dead weight weighting coefficient; k_QTaking 1.15 as a weighting coefficient of lifting load; k_WTaking 1 as a wind load weighting coefficient; m_G、M_Q、M_WThe dead weight of the crane, the lifting load and the moment of the wind load to the overturning edge are respectively.

3. The multimachine cooperative hoisting process of the box girder of the railway cutting highway bridge spanned over the under-construction according to claim 1, which is characterized in that: by means of a multi-machine cooperative hoisting system of a box girder of a railway cutting bridge striding over a building.

4. The utility model provides a cross under construction railway cutting highway bridge case roof beam multimachine hoist and mount system in coordination which characterized in that: the multi-machine cooperative hoisting system for the box girder of the over-crossing railway cut highway bridge comprises a gun carriage, a roadbed station crane C, a roadbed station crane B and a hoisting auxiliary device, wherein the gun carriage is arranged between a beam yard and a bridge site and used for transporting the box girder to a hoisting area; and the hoisting auxiliary device is provided with a hoisting point A and a hoisting point B at two ends.

5. The multimachine cooperative hoisting system for the box girder of the railway cutting highway bridge spanned over the under-construction according to claim 4, wherein: the handling auxiliary device includes:

the supporting device is used for being sleeved on the box girder;

the balance monitoring device is used for monitoring whether the box girder is horizontal or not in the hoisting process;

the process base is used for supporting the box girder so as to facilitate installation;

and the movable lifting lug device is used for changing the position of the lifted suspension.

6. The multimachine cooperative hoisting system for the box girder of the railway cutting highway bridge spanned over the under-construction according to claim 1, wherein: the supporting device comprises two side supporting frames and a middle supporting frame between the two side supporting frames; the two side supporting frames and the middle supporting frame are connected into a whole through a side connecting rod; side central openings corresponding to the box girder are arranged on the side supporting frames and the middle supporting frame; side central openings of the side support frames are provided with side stop blocks for placing the box girder to longitudinally slide out through bolts, and side fixing hanging rings are arranged on the two side support frames and the middle support frame;

the balance monitoring device comprises a monitoring lifting guide frame vertically arranged on the supporting device; a monitoring articulated shaft is arranged in the monitoring elevating guide frame in an elevating way, a monitoring lower pressure head used for pressing the upper surface of the box girder is arranged at the lower end of the monitoring articulated shaft, a monitoring side vertical frame is vertically arranged at one side of the monitoring lower pressure head, a monitoring horizontal vertical cross rod is vertically arranged on the monitoring side vertical frame, and a monitoring swing rod is arranged at the lower end of the monitoring horizontal vertical cross rod in a swinging way; a vertical marking line is arranged on the monitoring side vertical frame, and whether the box girder is horizontal or not is judged by observing the swing of the monitoring swing rod relative to the vertical marking line;

the movable lifting lug device comprises a lifting lug longitudinal moving frame which is longitudinally arranged on the supporting device; the lifting point A and the lifting point B are arranged at two ends of the lifting lug longitudinal moving frame; the lifting lug longitudinal moving frame is driven by a push rod to move longitudinally and is provided with a moving lifting lug seat;

a lifting lug B end limiting block is arranged at the lifting point B, and a lifting lug B end transverse stop rod for stopping the movement of the movable lifting lug seat is arranged at the output end of the lifting lug B end limiting block;

the hoisting point A and the hoisting point B have the same structure; the output end of the lifting point A is provided with a transverse stop lever at the end A of the lifting lug for stopping the movement of the movable lifting lug seat;

the auxiliary positioning device comprises an auxiliary support arranged on the supporting device, an auxiliary rotating shaft driven by a motor in a transmission way is arranged on the auxiliary support, an auxiliary swing arm driven by the auxiliary rotating shaft to swing, and a traction rope is connected below the auxiliary swing arm in a swinging way;

the bottom of the supporting device is provided with a roller;

a winch is arranged on the gun carriage, and a traction rope is connected to the winch;

the winch draws the box girder to be axially positioned and close to the adjacent connecting body through the traction rope.

Technical Field

The invention relates to a multi-machine cooperative hoisting system and a multi-machine cooperative hoisting process for a box girder of a cut highway bridge striding over a building railway.

Background

The railway in a certain area is a deep cutting section, the cutting side slope height is 27.7m, the cutting side slope is divided into four grades, and the slope rate is 1: 1.25. According to the design, after the railway cutting main body engineering is completed, the upper cross railway highway bridge is built to recover the existing highway engineering. The schematic diagram of the bridge site is shown in FIG. 1. The upper-span highway bridge is a simply-supported continuous prestressed reinforced concrete box girder bridge, the bridge span is arranged to be 3 x 40m, and the crossing angle with the railway is 90 degrees. The bridge width is 7m, two box girders are transversely arranged at each span, the girder width is 3.1m, and the pier height is 25.7 m. The layout of the bridge type of the highway is shown in figure 2. Two beam making yards are respectively arranged on the right side of the DK166+800 and the left side of the DK166+900, and a passage is repaired to an existing road and is transported to the top of a bridge head through the existing road for erection.

Because the box girder is long in length and heavy and is transported by the graben, the box girder belongs to translation hoisting. If the hoisting operation radius of the crane is too large when the crane operates at the cutting top, the hoisting operation is difficult to realize; if the crane hoists on the roadbed, the transverse distance between the slope toe and the abutment reaches 43m, and the vertical height reaches 27.7m, so that the operation radius and the hoisting height of the crane are both too large, and the realization is difficult. In addition, the crane operates in a deep cutting, piers exist in the operating range, and lifting points need to be changed in the multi-machine lifting process, so that the risk of collision among the suspension arms, the piers and the beams and among the suspension arms of the crane is high.

Common simply supported box girder erection methods include a bridge girder erection machine method, a cast-in-place method and a hoisting method. When the precast beam is adopted to cross the railway business line, a bridge girder erection machine or a crane is generally adopted to erect the beam. The railway management department generally preferentially selects a bridge girder erection mode on the basis of safety consideration of a railway business line on the premise of permission of conditions. When the bridge erecting condition of the bridge erecting machine is not met, the mode of erecting the bridge by the crane can be considered.

The bridge girder erection machine method is suitable for erecting box girders with more spans. The invention has less spans, only three spans and inconvenient traffic on a hoisting site, and if the bridge girder erection machine is adopted for construction, construction roads and splicing platforms need to be built; in addition, the assembly and disassembly of the bridge girder erection machine need the cooperation of a large-tonnage crane, more specialized personnel are equipped, and the engineering cost is higher. The cast-in-place construction method has large field operation amount, has cross operation with slope protection and drainage engineering, also influences the development of subsequent procedures and is difficult to ensure the construction period. The crane hoisting method has small field operation amount and small influence on the construction of railway engineering under construction; by parallel operation, the highway can be opened as early as possible, and the influence on local traffic is small. Therefore, the invention adopts a crane hoisting scheme, and the hoisting equipment adopts an all-ground truck crane.

Disclosure of Invention

The invention aims to solve the technical problem of providing a multi-machine cooperative hoisting system and process for a box girder of a road cutting bridge striding over a built railway. A multi-machine cooperative hoisting process for box girders of a railway cut highway over a construction site is characterized in that a cut top station crane A positioned at the slope top of a roadbed slope, a roadbed station crane C and a roadbed station crane B positioned at a bridge site hoisting area are used, a prefabricated beam field is arranged at the cut top beside the bridge site, and a gun carriage used for conveying the box girders to the hoisting area is arranged between the beam field and the bridge site; a hoisting point and B hoisting points are preset at two ends of the box girder; a middle span is preset in the middle of the bridge pier, side spans are arranged at two ends of the middle span, and the position of a roadbed slope top is positioned at a cutting top station;

the method comprises the following steps;

step one, executing an edge-span box girder hoisting scheme.

As a further improvement of the above technical solution:

the roadbed station crane C and the roadbed station crane B are both positioned on the roadbed, and the cut top station crane A is positioned at the top of the cushion; determining a station position according to the operation condition and the performance parameters of the crane; then, a gun carriage is used for pushing a delivery box girder backwards from an existing road at the bridge head, when the left end of the girder approaches to a bridge platform, a graben station crane A hooks a lifting point A at the left end of the box girder to test lifting, after safety and stability are confirmed, the lifting is started, and the tail of the gun carriage is evacuated; secondly, the graben station crane A is matched with the gun carriage to continue to translate the delivery box girder; thirdly, when the gun carriage approaches the bridge platform, the roadbed station crane B and the roadbed station crane C hook the lifting point A at the left end of the box girder through the balance beam, the graben station crane A changes the hook and hooks the lifting point B at the right end of the box girder, and after the lifting point conversion is realized, the gun carriage is removed; afterwards, the roadbed station crane B, C and the cutting station crane A cooperatively operate to translate the box girder to be in place;

step two, executing a mid-span box girder hoisting scheme; firstly, a gun carriage is used for reversely pushing a delivery box girder along an existing road and an erected side span box girder at the bridge head; then, when the left end of the box girder to be hoisted approaches the left end of the right cross box girder in the first step, the roadbed station crane B hooks the hoisting point A at the left end of the box girder, and the tail of the gun carriage is withdrawn; secondly, continuously translating the delivery box girder by the roadbed station crane B in cooperation with the gun carriage; thirdly, when the gun carriage approaches the left end of the right span box girder in the first step, the roadbed station crane C hooks the lifting point A at the left end of the box girder, the roadbed station crane B changes the hook and hooks the lifting point B at the right end of the box girder, and after the lifting point conversion is realized, the gun carriage is withdrawn; later, the box girders are translated into position by the two machines of the roadbed station crane B, C in cooperation.

The invention has the beneficial effects that: by adopting the method that the graben and the base surface multi-station multiple cranes feed beams in cooperation with the gun trucks, the problem that the cranes are difficult to horizontally move and hoist due to long beam length and heavy weight when the box girder of the deep cutting highway bridge striding over the railway under construction is erected can be solved. A QAY200 type crane and a QAY650 type crane are selected, the steel wire rope can meet the requirement of hoisting capacity, and the operation safety is ensured. The bearing capacity of the foundation needs to meet the hoisting requirement. The anti-overturning stability of the crane meets the requirement, and the construction safety can be ensured. Practice proves that the multi-machine cooperative hoisting technical method for the large-span box girder of the overpass railway under construction deep cutting highway bridge is novel, practical, safe, reliable and good in application effect. The invention has the advantages of reasonable design, low cost, firmness, durability, safety, reliability, simple operation, time and labor saving, capital saving, compact structure and convenient use.

Drawings

FIG. 1 is a schematic diagram of an overview of a bridge site of the present invention. Fig. 2 is a diagram of a highway bridge type layout of the present invention. Fig. 3 is a flow chart of a feeding beam hoisting process of the three-machine cooperation gun carriage. Fig. 4 shows the crane A, B, C of the present invention in place with a transfer car. Fig. 5 is a crane a of the present invention in conjunction with a gun carriage feed beam. Fig. 6 is a three-machine cooperative gun carriage feed beam of the present invention. Fig. 7 is the crane a unhooking of the invention. Figure 8 is the gun carriage evacuation of the present invention. Fig. 9 is a three-machine cooperative translation hoisting of the present invention. Fig. 10 is a flow chart of the feeding beam hoisting process of the double-machine cooperative gun carriage. Fig. 11 shows the crane B, C of the present invention in place with a transfer car. Fig. 12 is a crane B of the present invention in conjunction with a gun carriage feed beam. Fig. 13 is the crane B unhooking of the invention. Figure 14 is the gun carriage evacuation of the present invention. Fig. 15 shows the double-machine cooperative translation hoisting of the present invention. Fig. 16 is a schematic view of the box girder suspension point of the present invention. Fig. 17 is a schematic view of the crane of the present invention under operational stress. Fig. 18 is a schematic view of the crane of the present invention. Fig. 19 is a schematic view of the handling aid of the present invention. Figure 20 is an exploded schematic view of the handling aid of the invention. FIG. 21 is a schematic view of a side connector bar of the present invention. Figure 22 is a schematic view of a gun carriage of the present invention. Fig. 23 is a schematic view of the present invention. FIG. 24 is a geometric model diagram of the side span box girder hoisting calculation of the present invention. FIG. 25 is a geometric model diagram of the side span box girder hoisting calculation of the present invention.

Detailed Description

Referring to fig. 1-25, in the multi-machine cooperative hoisting process of the box girder of the over-spanning railway cutting highway bridge of the embodiment, as shown in fig. 1, by means of a cutting station crane a40 located at the top of a roadbed slope, a roadbed station crane C2 and a roadbed station crane B3 located at a bridge site hoisting area, a precast beam yard is arranged at the top of the bridge site, and a gun carriage 38 for transporting the box girder 1 to the hoisting area is arranged between the beam yard and the bridge site;

a hoisting point 9 and B hoisting point 10 are preset at two ends of the box girder 1; a middle span 5 is preset in the middle of the pier 4, side spans 6 are arranged at two ends of the middle span 5, and the position of a slope top of the roadbed slope at a cutting station is cut;

the method comprises the following steps;

step one, executing an edge-span box girder hoisting scheme.

The roadbed station crane C2 and the roadbed station crane B3 are both positioned on a roadbed, and the moat station crane A40 is positioned at the top of the cushion; determining a station position according to the operation condition and the performance parameters of the crane; then, the gun carriage 38 is used for pushing the delivery box girder 1 backwards from the existing road 8 at the bridge head, when the left end of the girder is close to the bridge abutment, the graben station crane A40 hooks the lifting point A at the left end A of the box girder to test lifting, after safety and stability are confirmed, the lifting is started, and the tail part of the gun carriage 38 is withdrawn; secondly, the graben station crane A40 cooperates with the gun carriage 38 to continue to translate the delivery box girder; thirdly, when the gun carriage 38 approaches the bridge platform, the roadbed station crane B and the roadbed station crane C hook the lifting point A9 at the left end of the box girder through the balance beam, the graben station crane A changes the hook and hooks the lifting point B10 at the right end of the box girder 1, and after the switching of the lifting points is realized, the gun carriage 38 is evacuated; afterwards, the roadbed station crane B, C and the cutting station crane A cooperatively operate to translate the box girder to be in place;

step two, executing a mid-span box girder hoisting scheme; firstly, a gun carriage is used for reversely pushing a delivery box girder along an existing road and an erected side span box girder at the bridge head; then, when the left end of the box girder 1 to be hoisted approaches the left end of the right cross box girder in the first step, the roadbed station crane B hooks the hoisting point A9 at the left end of the box girder, and the tail part of the gun carriage is withdrawn; secondly, continuously translating the delivery box girder by the roadbed station crane B in cooperation with the gun carriage; thirdly, when the gun carriage approaches the left end of the right span box girder in the first step, the roadbed station crane C hooks the lifting point A at the left end of the box girder by a lifting point 9, the roadbed station crane B changes the hook and hooks the lifting point B at the right end of the box girder by a lifting point 10, and after the lifting point conversion is realized, the gun carriage is withdrawn; later, the box girders are translated into position by the two machines of the roadbed station crane B, C in cooperation.

The prefabricated box girder belongs to a simply supported component, and in order to ensure that the stress point and the stress state of the box girder in the hoisting process are consistent with those of the box girder in use, a parallel hoisting two-point crane is adopted, so that the stress balance at the hoisting point in the hoisting process of the box girder and the stability of the hoisting girder and the girder falling are ensured. The distance between the lifting point and the two ends of the object takes the moment balance of the box girder as a calculation standard, namely, the positive and negative bending moments at the lifting point are ensured to be equal. Thus, two suspension points are provided at 0.2L from the beam end, respectively. See fig. 16. The hoisting point is in a steel wire rope binding pocket hoisting type. The weight of each box girder in the engineering is 161.2t, and the theoretical bearing capacity of two lifting points under the condition of double-machine lifting is 80.6 t.

And step B1, selecting the type of the roadbed station crane B and the roadbed station crane C.

The plane relation of the working condition CZ3 crane, beam and environment is shown in the figure.

The lifting capacity of the roadbed station crane B and the roadbed station crane C are the same, and both the roadbed station crane B and the roadbed station crane C have the same lifting capacity requirement

G_jBC＝K₁K₂G₀(3.1)

In the formula, G₀The sum of the weight of the hoisted objects, the weight of the lifting lugs and the weight of the rigging shared by the crane, G₀＝161.2/2+2.0＝82.6t；K₁Taking the dynamic load coefficient as 1.1; k₂For double-crane liftingThe unbalance coefficient is 1.2, and G is obtained by calculation_jBC＝109.0t。

Working range R of crane B_BShould satisfyHeight of lift H_BShould satisfy H_B> 33.0 m. Working range R of crane C_CShould satisfy

Height of lift H_CSame as H_B。

According to G_jBC、R_B、H_B、R_C、H_CConsidering that the crane B, C is of the same type, referring to a crane performance table, the crane B, C can be a QAY500 type truck crane, and the working conditions of the hoisting capacity G of 118t, the working amplitude R of 20m and the arm length L of 48m are selected, so that the hoisting height is selected

The hoisting requirement can be met.

Step B2, selecting type A of the graben station crane

And determining the performance parameter requirement of the crane A after determining the lifting point switching position of the working condition CB2 according to the performance parameters of the crane B, C. The plane relation of the working condition CB2 crane, the beam and the environment is shown in the figure.

The lifting capacity requirement of the crane B, C after the lifting point conversion is that

G_jBC＝K₁K₂G₀(3.2)

In the formula, G₀The sum of the weight of the hoisted object, the weight of the lifting lug and the weight of the rigging shared by the crane B, C, G₀＝161.2/2/2+2.0＝42.3t；K₁、K₂Respectively, the dynamic load coefficient and the unbalance coefficient are respectively 1.1 and 1.2. Calculated to obtain G_jBC60.9 t. According to the QAY500 type automobile crane performance table, the crane B, C has the working conditions of hoisting capacity G69 t and arm length L66 m and hoisting height

The corresponding maximum operating amplitude R is 30 m.

According to the calculation, the minimum working amplitude R of the crane A is required to realize the lifting point conversion of the working condition CB2 crane B, C and the crane A_ANot less than 17.64 m. The lifting capacity of the crane A is calculated by the same formula (3.1), and G can be obtained_jA109.0 t. Referring to a crane performance table, a QAY500 type automobile crane is selected, the working condition that the lifting capacity G is 138t, the working amplitude R is 18m and the arm length L is 30m is used, and the lifting height is used

Can meet the hoisting requirement.

The same model should be selected as much as possible for the crane used in the project, which is convenient for cooperative operation.

First, the calculated load G of the suspended object is determined_j

G_j＝K₁K₂G₀(1)

In the formula, G₀Taking 82.6t as the sum (t) of the weight of the hoisted object, the weight of the lifting lug and the weight of the rigging; k₁Taking the dynamic load coefficient as 1.1; k₂Taking 1.2 as the imbalance coefficient of double-crane lifting, and calculating to obtain G_j＝109.0t。

Then, according to the crane parameters, selecting the rated lifting capacity Q to be more than or equal to G_j. On the premise of meeting the lifting weight, the length L and the working radius R of the suspension arm are selected according to the lifting height H and the field condition. And calculating the operation radius and the lifting height of each crane according to different working conditions according to the lifting process.

According to the requirements of the crane performance parameters, performance tables of cranes with different tonnages are consulted for comparative analysis, and economic factors are considered on the premise of meeting the lifting weight requirement, wherein the crane A is a QAY200 type crane, and the crane B, C is a QAY650 type crane.

Steel wire rope type selection

The use standard of the large-diameter steel wire rope is

In the formula, D is the minimum diameter (mm) which is required by the hoisting steel wire rope; q is the crane bearing weight (t); beta is the load distribution coefficient, and is generally 66%. Considering the unbalanced coefficient K of the double-crane lifting, the general value is 1.2, and the value is taken under the working condition of the multi-crane lifting

Q＝80.6×1.2＝96.7t,

D is calculated according to the formula (2)_minShould reach 60 mm.

Unilateral single strand wire rope stress F_NCalculated by the following formula

In the formula, 1.05 is an included angle coefficient; q is the bearing weight (t) of the crane sling, and 97.2t is taken. Calculated to obtain F_N＝25.4t。

Sum of tensile forces

Z_n＝K×F_N(4)

And in the formula, k is the safety coefficient of hoisting the steel wire rope, and is 10. Calculated to obtain the total tension Z_n2489.2 kN. The steel wire rope is a fiber core, so the breaking tension needs to be converted and converted into a formula

Where α is a conversion factor and 1.226 is taken, the breaking tension of the steel cord is obtained as Z2030.3 kN. Breaking tension according to document [8]

Wherein Z is breaking tension (kN); f_CTaking 1670kg/mm as tensile strength of the steel wire rope²And D is calculated to be 65 mm.

Through the analysis and calculation, the steel wire rope is selected from phi 65-6 multiplied by 19zs + FC-1670.

Bearing capacity of supporting leg foundation

According to the hoisting scheme, the crane A, B has equal load bearing capacity. The total bearing weight N of a single crane foundation is calculated according to the following formula

In the formula, gamma_G、γ_QTaking the static load and dynamic load combination coefficients as 1.2 and 1.4 respectively; g₀The sum (kN) of the weight of the crane, the super-lift counterweight, the sling and the rigging, is the same for the model B, C of the crane,

G₀＝2855.7kN；

G_Lthe weight of the box girder is 789.9 kN.

The total load bearing N is calculated to be 3979.8 kN.

Assuming that four supporting legs of the crane are uniformly stressed, the average compressive stress applied to the foundation by each supporting leg is

Wherein A is the area (m) of the steel backing plate of the crane support leg²) The leg pad was made of 2.5m × 3.0.0 m × 0.05.05 m steel plate, and calculated to be 132.7 kPa.

Considering the construction of the upper-span railway girder erection and taking 1.2 times of safety factor, the bearing capacity requirement of the operation site is f_a1.2p ≧ 159.2 kPa. If the bearing capacity of the foundation on site does not meet the requirements, treatment measures such as tamping or replacing and the like can be adopted.

Analysis of hoisting safety

In order to ensure the stability of the crane in the hoisting process, the anti-overturning stability of the crane needs to be analyzed. The standard of the anti-overturning stability of the crane is

∑M＝K_G·M_G+K_Q·M_Q+K_W·M_W≥0 (9)

Wherein ∑ M is the anti-overturning moment, K_GTaking 1 as a dead weight weighting coefficient; k_QTaking 1.15 as a weighting coefficient of lifting load; k_WTaking 1 as a wind load weighting coefficient; m_G、M_Q、M_WFrom crane to craneThe moment (kN m) of heavy load, lifting load and wind load to the overturning edge. The crane works under a force diagram as shown in figure 17. In the figure, G-crane dead weight (kN); q-hoist weight (kN); w-wind dynamic load (kN), considered as 20% of the weight of the load; a is the distance (m) from the gravity center of the crane to the overturning fulcrum of the support leg; r is the crane operation radius (m); h is the height (m) of the wind power loading resultant force point.

The QAY650 type crane G is 291.4t, a is 5m, R is 40m, Q is 20.7t, W is 4.14t, the center of gravity of the suspended object is taken as the pneumatic loading resultant force point, h is 26.7m, and the calculation can obtain the weight of the suspended object

And sigma M is 513.3kN M & gt 0, and the requirement is met.

Similarly, for the QAY200 type crane, the sigma M is 77.3kN M is more than 0, and the requirement is met.

A multi-machine cooperative hoisting process for box girders of a highway bridge of a railway crossing over a building includes the steps that a box girder station crane A positioned on an existing road at a bridge head, a roadbed station crane C and a roadbed station crane B positioned at a bridge site hoisting area are used, a prefabricated beam field is arranged beside the bridge site, and a gun truck for conveying the box girders to the hoisting area is arranged between the beam field and the bridge site;

a hoisting point and B hoisting points are preset at two ends of the box girder; a middle span is preset in the middle of the bridge pier, side spans are arranged at two ends of the middle span, and a cutting top station is arranged at the bridge head and has a road;

the method comprises the following steps;

step one, executing a side span box girder hoisting scheme; firstly, a roadbed station crane C and a roadbed station crane B are both positioned on a roadbed, a cut station crane A is positioned on an existing bridge head road, and a station position is determined according to operation conditions and crane performance parameters; then, a cannon car is used for reversely pushing a delivery box girder from an existing road at the bridge head, when the left end of the girder is close to a cutting station of the existing road at the bridge head, a cutting station crane A hooks a lifting point A at the left end of the box girder to test lifting, after safety and stability are confirmed, the lifting is started, and the tail part of the cannon car is withdrawn; secondly, the graben station crane A is matched with the gun carriage to continue to translate the delivery box girder; thirdly, when the gun carriage approaches the cut top to a preset position, the roadbed station crane B and the roadbed station crane C hook the lifting point A at the left end of the box girder through the balance beam, the cut top station crane A changes the hook and hooks the lifting point B at the right end of the box girder, and after the lifting point conversion is realized, the gun carriage is removed; afterwards, a graben station crane A and a roadbed station crane B, C cooperate to move the box girder in place;

step two, executing a mid-span box girder hoisting scheme, and firstly, pushing the delivery box girder backwards by using a gun carriage along the existing road at the bridge head and the erected box girder; then, when the left end of the box girder to be hoisted approaches the left end of the right cross box girder in the first step to a preset position, a roadbed station crane B hooks a hoisting point A at the left end of the box girder, and the tail of the gun carriage is withdrawn; secondly, continuously translating the delivery box girder by the roadbed station crane B in cooperation with the gun carriage; thirdly, when the gun carriage approaches the left end of the right cross box girder in the first step to a preset position, the roadbed station crane C hooks the lifting point A at the left end of the box girder, the roadbed station crane B changes the hook and hooks the lifting point B at the right end of the box girder, and after the lifting point conversion is realized, the gun carriage is withdrawn; later, the box girders are translated into position by the two machines of the roadbed station crane B, C in cooperation.

Installing a hoisting positioning device 11 on the beam 1; secondly, the crane C and the crane B respectively hook the lifting point A9 and the lifting point B10 of the box girder 1, wherein the steel wire rope of the crane A is connected with the movable lifting lug seat 31 positioned at the lifting point B10, test lifting is carried out, after safety and stability are confirmed, lifting is started, the included angle between the monitoring side vertical frame 26 and the monitoring swinging rod 28 is observed, observation of the box girder 1 is realized, and whether the box girder is lifted correctly or not is determined.

When the lifting lug position is changed, the movable lifting lug seat 31 moves to the lifting point A9 and is blocked by the transverse blocking rod 33 at the end A of the lifting lug to realize that the crane A or C is hooked and hung at the lifting point A9 or B10;

when the installation needs to be lowered, the auxiliary rotating shaft 35 drives the auxiliary swing arm 36 to swing upwards, and the longitudinal position is adjusted through the traction of the winch.

Before the step one, the method comprises the following steps:

step A, determining the position of a lifting point, namely, ensuring that positive and negative bending moments at the lifting point are equal based on the distance between the lifting point and two ends of an object by taking the moment balance of a box girder as a calculation standard, wherein the two lifting points are respectively arranged at a position 0.2L away from the girder end, and the lifting point adopts a steel wire rope binding pocket hanging type;

b, selecting a crane model;

first, the calculated load G of the suspended object is determined_j

G_j＝K₁K₂G₀(1)；

In the formula, G₀The sum of the weight of the hoisted object, the weight of the lifting lug and the weight of the rigging; k₁Taking the dynamic load coefficient as 1.1; k₂Taking 1.2 as the imbalance coefficient of double-crane lifting;

then, according to the crane parameters, selecting the rated lifting capacity Q to be more than or equal to G_jOn the premise of meeting the lifting weight, selecting the length L and the working radius R of the suspension arm according to the lifting height H and the field condition, and calculating the operation radius and the lifting height of each crane according to different working conditions according to a lifting process;

according to the requirements of crane performance parameters, looking up performance tables of cranes with different tonnages for comparison analysis, and selecting a crane;

specifically, the crane performance parameters include a lifting height, a working radius, a lifting weight and the like. The working radius of the crane is used for determining the lifting capacity_A、R_BThe minimum, namely the minimum tonnage of the crane is an optimization target. The station position of the crane is described by the distance x and y from the central line of the road, and the x and y are optimization variables. Preferably, the method comprises the following steps:

step B1, optimizing the model by the crane B; firstly, according to the comprehensive analysis of the operation condition of the crane, a geometric model diagram is calculated according to the hoisting of a midspan box girder, the station position of the crane B is taken as an optimization variable, and on the premise of ensuring safe hoisting, the optimized mathematical model is established as follows by taking the minimum operation radius of the crane, namely the minimum tonnage of the crane as an optimization target:

min R_B(3.1)

formulas 3.2a to 3.2C are respectively the lifting distance, height and lifting capacity conditions of the crane B under the working condition C1, formula 3.2d is the anti-collision condition of the crane B under the working condition C3, and formulas 3.2e to k are respectively the hoisting distance, height and lifting capacity conditions of the crane BB, the ranges of station positions and variable amplitude angles under two working conditions; x is the number of_B、y_BRespectively the transverse distance and the longitudinal distance m of the crane in a coordinate system; a is the center position m of the left end of the midspan box girder; l is the length of the box girder, m; l is_BThe length of the crane jib is m; theta_CZ1θ_CZ3The working condition is the amplitude change angle and degree of the CZ1 and CZ3 cranes; h_BIs H_Pier+H_Rope+H_Cover+H _Beam33, m; g is the lifting weight of the crane, t; g₀Load for a single crane, t; p_BThe minimum distance between a crane jib and a box girder in the translation process is P_B＞0，m。

Step B2, according to the comprehensive analysis of the crane operation condition, calculating a geometric model diagram according to the mid-span box girder hoisting, taking the station position of the crane C as an optimization variable, and on the premise of ensuring safe hoisting, taking the minimum radius of the crane operation, namely the minimum tonnage of the crane as an optimization target, establishing an optimization mathematical model as follows:

min R_C(3-3)

formulas 3.2a to 3.2C are respectively the hoisting distance, height and hoisting capacity conditions of the crane C under the working condition CZ3, and formulas 3.2d to g are the ranges of the station position and the amplitude variation angle of the crane C;

respectively the transverse distance and the longitudinal distance m of the crane in a coordinate system; a is the center position m of the left end of the midspan box girder; l is the length of the box girder, m; l is_{Arm C}The length of the crane jib is m; theta_Z3The amplitude change angle is set as the amplitude change angle of the crane under the CZ3 working condition; h_CIs H_Pier+H_Rope+H_Cover+H _Beam33, m; g is the lifting weight of the crane, t; g₀Is the load of a single crane, t.

Step B3, selecting and analyzing the model of the crane B, C; a general description of the constrained optimization problem is:wherein x is [ x ]₁,x₂,Λ,x_n]^TThe objective function f (x) is minimized on the premise that the constraint G (x) ≦ 0 is satisfied. Aiming at the optimization model of the crane station, an Interior Point algorithm (Interior Point algorithm) in an fmincon function is adopted for solving, and when the optimization problem in practice is solved, a solving formula is as follows:

min f(x)

in the formula 4.1, Ax is less than or equal to b and A₁x＝b₁Is a linear constraint, C (x) is less than or equal to 0 and C₁(x) 0 is a non-linear constraint and LB ≦ x ≦ UB is a bounded constraint. The basic idea of the constrained optimization interior point algorithm is as follows: the constrained optimization problem is converted into an unconstrained problem by introducing a utility function method, the utility function is continuously updated by utilizing an optimization iteration process so as to enable the algorithm to be converged, and when an iteration point is close to a boundary, an objective function is unnecessarily increased to show punishment, so that the iteration point is prevented from crossing the boundary, and the optimal solution is ensured to be in a feasible domain.

Step B4, calculating and solving an optimized mathematical model established in the process of lifting the side span box girder step by step through the Interior Point algorithm, namely selecting a proper lifting capacity in a crane performance table, obtaining the arm length and the working radius corresponding to the lifting capacity, substituting the arm length and the working radius into the optimized model for calculation, and obtaining a B, C crane model selection and station configuration scheme as follows:

(1) type B selection of crane

TABLE 4-1 Crane B model calculation results Table

Aiming at the model selection optimization of the crane B, when QAY300 type crane parameters are used for calculation, the objective function has no solution, the QAY300 type crane performance can not meet the working condition requirements, and therefore the crane configuration combination is eliminated; both the QAY650 type crane and the QAY500 type crane meet the requirements, and in consideration of economy, the QAY500 type crane is selected for hoisting by the crane B, and the distances x and y from the crane B to the central line of the highway are respectively 13.27m and 7 m.

(2) Type C selection of crane

TABLE 4-2 Crane C model calculation results Table

Aiming at the model selection optimization of the crane C, when QAY300 type crane parameters are used for calculation, the objective function has no solution, the QAY300 type crane performance can not meet the working condition requirements, and therefore the crane configuration combination is eliminated; both the QAY650 type crane and the QAY500 type crane meet the requirements, and due to the economical consideration, the crane C selects the QAY500 type crane to hoist, and the distances x and y from the crane C to the central line of the highway are respectively 4.37m and 7 m.

Step B5, the crane A type selection analysis,

the results of the mid-span type selection analysis show that the cranes B, C all use QAY500 type cranes, and the crane a is selected on the basis of mid-span type selection.

G_j＝K₁K₂G₀(4.2)

In the formula, G₀The sum (t) of the weight of the hoisted object, the weight of the lifting lug and the weight of the rigging is obtained, 42.1 t is obtained by the crane B, C, and 82.6t is obtained by the crane A; k₁Taking the dynamic load coefficient as 1.1; k₂Taking 1.2 as the imbalance coefficient of double-crane lifting, G of the crane B, C can be obtained by calculation_j46.3t Crane A G_j＝109.0t。

On the basis that the model of the crane B, C is QAY500, a crane performance table is referred, and the rated hoisting capacity Q is selected to be more than or equal to G_j. On the premise of meeting the lifting weight, the length L and the working radius R of the suspension arm are selected according to the lifting height H and the field condition. The crane B, C should be fullH is more than or equal to 33m, G is more than or equal to 46.3t, the crane A can meet the condition that G is more than or equal to 109.0t, and analysis can obtain:

the crane B, C is preferably selected from the group consisting of R38 m, L72 m,

46t is more than 40.5t, the crane A adopts a QAY300 type, R is 8m, L is 25.7m,

G＝103t＞101.25t。

according to the calculation and analysis, the lifting point conversion is carried out when the left end of the lifted side span box girder is 11m away from the graben.

In summary, for the reasons of safe construction and economy and the performance parameter requirements of the cranes under various working conditions, the crane B, C is selected to be the QAY500 type crane, and the crane a is selected to be the QAY300 type crane.

Step C, selecting the type of the steel wire rope

First, the use criteria of the large diameter wire rope are

In the formula, D is the minimum diameter which is required to be met by the hoisting steel wire rope; q is the bearing weight of the crane; beta is the load distribution coefficient, and is generally 66%. Considering the unbalanced coefficient K of the double-crane lifting, the general value is 1.2, and the value is taken under the working condition of the multi-crane lifting

Q＝80.6×1.2＝96.7t,

Then, D is calculated from the formula (2)_min；

Secondly, the single-sided single-strand wire rope is stressed by F_NCalculated by the following formula

In the formula, 1.05 is an included angle coefficient; q is the bearing weight of the crane sling;

sum of tensile forces

Z_n＝K×F_N(4)

In the formula, k is the safety coefficient of hoisting the steel wire rope, and 10 is taken;

thirdly, the steel wire rope is a fiber core, so the breaking tension is converted into a conversion formula

Wherein α is a conversion coefficient, 1.226 is taken, and breaking force is calculated as

Wherein Z is breaking tension; f_CTaking 1670kg/mm as tensile strength of the steel wire rope²；

Through the analysis and calculation, the steel wire rope selects phi 65-6 multiplied by 19zs + FC-1670;

step D, calculating the bearing capacity of the landing leg foundation,

first, the crane C, B bears equal weight as seen in the hoisting scheme. The total bearing weight N of a single crane foundation is calculated according to the following formula

In the formula, gamma_G、γ_QTaking the static load and dynamic load combination coefficients as 1.2 and 1.4 respectively; g₀The sum of the weight of the crane, the super-lifting counterweight, the sling and the rigging is same for the model B, C of the crane, G_LIs the weight of the box girder;

then, assuming that the four legs of the crane are uniformly stressed, the average compressive stress applied to the foundation by each leg is

Wherein A is the area (m) of the steel backing plate of the crane support leg²)；

Secondly, considering the construction of the upper-span railway girder erection, the bearing capacity of the operation field is 1.2 times of the safety coefficientRequirement is f_aThe bearing capacity of the foundation on site can not meet the requirement, and a treatment measure of tamping or replacing and filling can be adopted;

step E, hoisting safety analysis

Firstly, the crane anti-overturning stability standard is

∑M＝K_G·M_G+K_Q·M_Q+K_W·M_W≥0 (9)；

Wherein ∑ M is the anti-overturning moment, K_GTaking 1 as a dead weight weighting coefficient; k_QTaking 1.15 as a weighting coefficient of lifting load; k_WTaking 1 as a wind load weighting coefficient; m_G、M_Q、M_WThe dead weight of the crane, the lifting load and the moment of the wind load to the overturning edge are respectively.

By means of a multi-machine cooperative hoisting system of a box girder of a railway cutting bridge striding over a building.

A multi-machine cooperative hoisting system for a box girder of an over-built railway cutting highway bridge comprises a gun carriage, a roadbed station crane C, a roadbed station crane B and a hoisting auxiliary device, wherein the gun carriage is used for conveying the box girder to a hoisting area, and the hoisting auxiliary device is arranged between a beam yard and a bridge site; and the hoisting auxiliary device is provided with a hoisting point A and a hoisting point B at two ends.

The handling auxiliary device includes:

the supporting device is used for being sleeved on the box girder;

the balance monitoring device is used for monitoring whether the box girder is horizontal or not in the hoisting process;

the process base is used for supporting the box girder so as to facilitate installation;

and the movable lifting lug device is used for changing the position of the lifted suspension.

The supporting device comprises two side supporting frames and a middle supporting frame between the two side supporting frames; the two side supporting frames and the middle supporting frame are connected into a whole through a side connecting rod; side central openings corresponding to the box girder are arranged on the side supporting frames and the middle supporting frame; side central openings of the side support frames are provided with side stop blocks for placing the box girder to longitudinally slide out through bolts, and side fixing hanging rings are arranged on the two side support frames and the middle support frame;

the balance monitoring device comprises a monitoring lifting guide frame vertically arranged on the supporting device; a monitoring articulated shaft is arranged in the monitoring elevating guide frame in an elevating way, a monitoring lower pressure head used for pressing the upper surface of the box girder is arranged at the lower end of the monitoring articulated shaft, a monitoring side vertical frame is vertically arranged at one side of the monitoring lower pressure head, a monitoring horizontal vertical cross rod is vertically arranged on the monitoring side vertical frame, and a monitoring swing rod is arranged at the lower end of the monitoring horizontal vertical cross rod in a swinging way; a vertical marking line is arranged on the monitoring side vertical frame, and whether the box girder is horizontal or not is judged by observing the swing of the monitoring swing rod relative to the vertical marking line;

the movable lifting lug device comprises a lifting lug longitudinal moving frame which is longitudinally arranged on the supporting device; the lifting point A and the lifting point B are arranged at two ends of the lifting lug longitudinal moving frame; the lifting lug longitudinal moving frame is driven by a push rod to move longitudinally and is provided with a moving lifting lug seat;

a lifting lug B end limiting block is arranged at the lifting point B, and a lifting lug B end transverse stop rod for stopping the movement of the movable lifting lug seat is arranged at the output end of the lifting lug B end limiting block;

the hoisting point A and the hoisting point B have the same structure; and a lifting lug A end transverse blocking rod for blocking the movable lifting lug seat from moving is arranged at the output end of the lifting point A.

The auxiliary positioning device comprises an auxiliary support arranged on the supporting device, an auxiliary rotating shaft driven by a motor in a transmission way is arranged on the auxiliary support, an auxiliary swing arm driven by the auxiliary rotating shaft to swing, and a traction rope is connected below the auxiliary swing arm in a swinging way;

the bottom of the supporting device is provided with a roller;

a winch is arranged on the gun carriage, and a traction rope is connected to the winch;

the winch draws the box girder to be axially positioned and close to the adjacent connecting body through the traction rope.

The invention realizes the construction of the box girder 1 based on a crane C2 and a crane B3, skillfully realizes the automatic change of a hoisting point, realizes the installation of a middle span 5 and an edge span 6, realizes the installation and hoisting through the ingenious design of a cutting station 7, realizes the hoisting of a bridge head existing road 8, realizes the hoisting of an A hoisting point 9 and a B hoisting point 10, realizes the hoisting by taking a hoisting auxiliary device 11 as an invention point, realizes the support of the box girder, avoids the sinking deformation of the box girder caused by the traditional hoisting, thereby, through a support device 12 frame, the frame is preferably a detachable split structure, has good universality and adjustable length, finishes the stress, avoids the deformation, a balance monitoring device 13 can utilize the swing to realize the visual observation of an included angle by naked eyes, a process base 14 is conveniently supported off the ground, is convenient to assemble, a lifting lug device 15 realizes the position adjustment of a hoisting steel wire rope, an auxiliary positioning device 16 realizes the, avoid artifical the hook that trades, it is connected with the hoist engine through wire rope, realized that the case roof beam is close to longitudinal location, thereby solved the inconvenient technical problem of butt joint between the case roof beam, monitoring lift leading truck 23 realizes the direction, monitoring articulated shaft 24 has fine compatibility, thereby make pressure head 25 press on the case roof beam upper surface under the monitoring, thereby realized the perpendicular of monitoring side vertical frame 26, utilize monitoring swinging arms 28 (vertical state all the time) of wobbling on the horizontal vertical horizontal pole 27 of monitoring to realize perpendicular and vertical contained angle and adjust.